Locking device for screws and the like



J. GIBBONS 1,871,684

LOCKING DEVICE- FOR SCREWS AND THE .LIKE

Filed Nov. 29., 1930 f rm ewroe Patented Aug. 16, 1932 WILLIAM JAMES GIB BONS, OF PHILADELPHIA, "PENE!fiYIrVAINIA:-

LOCKING D-EV IGE FOR SCREWS AND THE IJKE Application filed November 29, 1930. Serial No. 488,869.

My invention relates to locking devices for screws and the like of the character shown in my previous Letters Patent of the United States, No. 1,707,933, issued April 2, 1929,

and it-has for its general object to provide a I novel device which is efiective as a locking instrumentality to prevent backing out or screws and; the like under any and all conditions. a

A further object of the invention is to pro". vide means whereby the locking washer may be rotatably adjusted with respect to the screw or the-like, even after the latter has been screwed down-so as to firmly clamp the 55 object, such, for example as an electric terminal, and various kinds of mechanical plates and parts which it. is intended'to hold and secure in position.

7 To the foregoing and other-ends my inventioncompreh-ends the construction and arrangement as hereinafter described in detail,

particularly pointed out in the claims and as illustrated in the drawing wherein it have illustrated certain embodiments of the inven- 'tioir-in the formwhichat present are pre-- ferred by me; but it will be understood that the invention is susceptible of embodiment in 'other'forms'of construction than are shown and thatchangesin the details of construction may be made within the scope of the claimsiwithout departing'fromthe invention.

In the drawing Fig. 1 is a view in top plan of a device embodyingthe invention, the same being shown 5 in connection'with an electric terminal and. a

support therefor; v

Fig-2 isa transverse section taken on the line 2- 2:of ig. 1; V a F 'g; 3'-is= aview in perspective of the-annnlar washer'device having projectingfingers which: are adapted to engage portions of the structureincluding the screw to prevent back: in%outrotation of the latter; a a 'i'g; 4 isa' view in top plan similar to that shown inFig. 1 but showinga modified arrangement for preventing unscrewing or backingout movement of the screw;

Figafrisa longitudinal sectional view taken on the angulandash line '55 of Fig. 4;

Fig; 611's.- aatop 'planview showing another 'bodying the invention;

modified 'construc-tionof an arrangement em- Fig. 7 is atransverse sectionalview taken on the line 7 -7 ofFi'g. 6; and V Fig. 8 is a sectional view showing still an, other modified construction of device .einbod'yingv the invention.

In the several forms of the device as illus trated, the construction ofthe annular look ing washer or element 1 is the same and it is 0 provided with fingers 2' and 3 which project outwardly from diametrically opposed points ofthe outer edge of said washer.

Referring now to Figs. 1 to ,7 inclusive, it will be noted'that I' have provided a screw havinga screw-threaded portion 1 and a head 5 which has a'lower portion 6 of less diameter than the adj oining:intermediateportion' 7, the latter being of" considerably greater 7 diameter than the portion 6. The difierence between the diameters of these two portions provides a shoulder at8. The underside of theportion 6 has an annular flat surface and the lower edge of the portion 6 is rounded as indicated at Qto facilitate the 7 entryof the portion6' into the opening of the annularfwasher 1.. The said openingis' ofai diameter slightly greater thanthat of the diameter of the portion 6'; inconseqnenee of which the washer maybe rotatably ad justed upon the said portion 6. Tli'eouter edge portion of the intermediate part 7 v of the'head of the screw may be regarded in effect as a flange and it is provided in its peripheral edge with notches 10'. These. 35 notches extend entlrely aroundthe peripheral edge of thjepart 7and are locatedat short intervals with respect to each other; The central'portion of theintermediate part 7.

is provided. witha projection llwhich: may so be dome-shaped or of any other desiredshape I having a" s'1ot or notch 12 adapt-ed to be engaged by a; suitable instrumentality, such! as a. screw-driver, for turning the screw; It will be understood that before insertinglithejoa screw into an opening the washer 1 is placed" in position thereon so thatwhen the screwis finaly screwed into its finalposition with the.- lower side of theiportionS clamped against the member to'b'e held the washer will be its Referring to Figsl 1 to 5 aterminal: 15"

of known construction is shown having a tubular portion 16 and a flattened portionl'i. The flattening out of the tubular portion 16 to form the flattened portion 17 provides a shoulder-like portion 18. ,The terminalis supported upon a support'20 which as illustrated is in the form of a'plate. It is provided with a screw-threaded opening 21 with which the screw-threaded portion 4 of the screw engages. The screw-threaded portion 4 of the screw passes through the opening provided in the flattened portion 17 of the terminal, and the under side of the portion 6 of the screw head clampsupon or against the upper side of the flat portion 17 and holds the terminal in any desired position. I

In the construction as shown in Figs. 1

.and 2, the plate'20 is provided with an opening 23 into which the finger 2 of the washer 1 is adapted to be inserted as shown in Fig. 2. The opposite finger 3 is bent upwardly into engagement with one of the slots in l the periphery of the intermediate or middle portion 7 of the screw head. The thickness of the washer 1 is slightly less than the length of the portion 6 of the head of the screw, in consequence of which the shoulder 8 does not clamp upon the said washer when the screw has been inserted as far as it will. go. It follows therefore that the washer 1 may be rotatably adjusted about the portion 6 so as to bring it into position to permit the ins'ertion of the fingeror projection 2 into the opening 23. With'the' said finger 2 pro jecting. into the opening 23 and with, the finger 3 bent upwardly into engagement with a notch 10 in the periphery of the middle or intermediate portion 7 of the screw, it

will be apparent that the screw is held against rotation and maintains its clamping relationship to the fiat portion 17 of the terminal so as to hold the latter against accidental movement. The underside of the outer edge portion of the intermediate part of the head 5 is beveled or curved upwardly as shown, so as to facilitate the bending of the finger 3 upwardly into one of the notches of said edge. When it is desired to turn the screw,

the finger 3 is merely bent downwardly out of the notch with which it is inengagement, whereupon the lower rounded portion of the head may pass thereover when the screw is turned.

The construction as illustrated in Figs. 4: and 5 is'identical with that'shown in Figs.

1 and 2 except that the plate or holder 20. is not provided with an opening corresponding to the opening 23, and to prevent rotation of the screw to effect backing out thereof the finger or projection 2 is positioned in contact with an edge of the shoulder 18 of the terminal 15 as indicated at 25. The projection 3, as in Figs. 1 and 2, is bent upwardly into engagement with one of the notches 10 as shownin Fig.5. It will be apparent that as long as the'finger or projection 3 remains in engagement with a notch as shown in Fig. 5, rotation of the screw in an anti-clockwise direction to effect backing out thereof is prevented.

In the construction as illustrated in Figs.

- 6 and 7 the plate or holder 30, having a screwthreaded opening 31 to receive the screwe threaded portion 4 of the screw, is somewhat thinner than the corresponding plate 20 of the preceding figures of the drawing and is provided with oppositely disposed projections- 32. In this construction, as in those illustrated' in Figs. 1, 2, 4 and 5, the washer is located upon the upper side of the fiat portion 17 of the terminal 15 with the portion .6- of' the screw head projecting into the opening of the washer 1. The washer 1 maybe adjusted in such positionupon the portion 6 that.

when the screw has been screwed into the holder 30 150 clamp againsttheflatportion 17 of the terminal to hold the latter in position,

the finger. or projection 2 will be located in contact with one of the projections 32 as shown in Fig. 7. lVith the finger or projection 3 in engagement withthe slot or notch 10 in the periphery of the middle portion7 of.

the screw it will be apparent that the screw I cannot be rotated in an anti-clockwise direction to effect backing out thereof. The contact of the finger 2 with a projection 32 at the right side of Fig.7 will prevent such rotailOE f tion. The same result would follow if the washer 1 were so adjusted as toplace thepro jection 2 in contact with the rear edge, having f reference to Fig.7 of the drawing, of the projection at the left hand side of Fig. 7.

In Fig. 8, I have shown a construction com-. l r

prising a cap-screw 35 employed for securing a plate 36 to a member 37, the latter having a screw-threaded opening 38 therein forthe 9 reception of and engagement with the-screwthreaded portion of the screw 35.' ,Thehead of the cap-screw hasa taperedreduced lower end portion 39, the said portion beinglinef- 7 fect'ofinverted truncated cone shape and of substantially less diameter than the remaining portion of the head. The lower edge of" the tapered portion 39 is slightly rounded as indicated at 39 The length of the portion 39 is slightly greater than that of the thick ness of the washer 1, in consequence of which when the'cap-screw is screwed into place as shown in Fig.8 with the tapered reduced portion 39 projecting through the opening of the washer 1, the shoulder 40 of the-head does not clampagainst the washer 1 so that the latter may be rotatably adjusted about the portion 39 to locate the finger or projection 2 in position to permit its insertion into the opening 41 in the plate 36. lVhen the finger 2 projects into the hole 41 and the finger 3 is bent upwardly into engagement with one of the notches 4-2 which are provided at intervals in the outer edge of the head of the screw, it will be apparent that-rotation of the screw relatively to the part36 is prevented. 7

of the finger 2 from the opening 23 or 41, or

away from the shoulder 18 or stop 32.

In the foregoing description of my invention I have described the washer l as being rotatably adjustable about the portions 6 and 39, setting forth that the adjustment of the washer may be effected after the screw is screwed into clamping position. In the use of the device, however, and in practice the finger 2 has been in the past and usually will be in the future bent into the opening 23 or 41 as the case may be,after which the screw will be screwed down into clamping position. In the construction embodying my present invention no clamping action or pressure is exerted upon the washer, in consequence of which there is no tendency of the outer edge of the washer to bend or curl upwardly and therefore the tongue or projection 2 remains in engagement with the hole or opening 23 or 41, or the stop 18 or 32, as the case may be; whereas. in previous constructions when the head of the screw clamped upon the washer to cause the outer edges thereof. in many cases, to curl or bend upwardly, the projections were withdrawn from the said openings. As a result of that occurrence, the device in some instances failed to perform its proper function of preventing rotation of the screw to prevent backing out thereof. It will be seen that I have illustrated two types of screws, namely, a machine screw and a cap screw, both of which are shown as having heads of upset type, but it will be understood that the invention is applicable to all kinds of screws, screw bolts and machine screw nuts, made by upsetting metods or milled from solid bars. v

Having thus described my invention what I claim and desire to secure by Letters Patent is: c

1. Screw locking means comprising a screw the lower side of the head of which consists of a portion of reduced diameter as compared hthe adjoin g, portion of he s idheadz nd a; astening:- a her, th t ickness f pon the said. reduced portion, said Washer having means for lockingengagement with a no o atab emem and alsohaving means for locking engagement withthe heard of sai s rew- Ser W leeki gln ns e ap singa crew h ving a hea ompr sing ,aelamping per-.-

n-up n it u de sid of less iameter han.

the: adjoiningupper portion, the under side" f adjoining upp p rtio constit ting.

a sh u d r, a an u a 'wa e moun d upon the fi s named P ri n ofz hesaid h ad and aving aickn ss e han hel ngthi ofsaid-clamping portion so as to be rotatahlyj t bl he n, the aid. adjoining upper portion of the head being providedwith;

t he n s pe iph y, the aid annula washer having a finger adapted to be bent t ngageme with any one fsai notches,-

h aid; Washe ha ng an he fing and i nery means with whic it e said other finger is adapted to. contact to prevent rotation fsa d c e o usebae ihgout; move,- ment thereof,

3- Se e k gmeans ompr sing a screw I the lev r ide of he he d f which is. pre= vided wi h a clamping pertienef. less; diam eter than the adjoining upper portion thereof the o er ut dge of he said portion of less, diameter being rounded and'the portion of the adjoining upperport-ion ofsaid head p je ting o twardly andfo ming a hou der, and a fastening washer; adjustably;

u ds p n the said clamping portion and having a thiclgiess less than the'length' of saidv clamping portion, said washer havingmeans for preventing rotation of tlie'said screw to unscrew the same.

4:. In a locking device for screws and the like, the combination of a screw having a head the lower side of which is provided with a clamping portion of less diameter than the adjoining upper portion thereof, the said head havlng notches in the outer edge thereof, an annularwasher mounted on the said clamping portion and having a thickness less than the length of said clamping portion, said washer having fingers projecting outwardly from the edge thereof one of said fingers adapted to be bent into engagement with one of said notches, a support, and an electric terminal mounted on said support and held in selected fixed position by said screw, the said terminal having a shoulder near the said screw with which the other of said fingers is adapted to contact to prevent rotation of said screw in a direction to cause backing out thereof.

5. In a locking device for screws and the like, the combination of a screw having a head the lower portion of which is of less diameter than the adjoining upper portion thereof and the outer edgeof'said headhaving notches therein, an annular washer mounted on the said portion of less diameter,"

-'said' support;

the length of the said portion of less diameter so that the washer may be rotatably ad'- justed upon said portion of less diameter,- the said washer having fingers which project outwardly from the outer edge thereof one of said fingers adapted to be bent into engagement with one of said notches, a support having a projection extending upwardly there-' from in spaced relation to the said screw, and

a member adapted to be secured and held'by said-screw on said support, the other of the fingers of said washer contacting With said projection to prevent rotation of said screw in a direction to cause backing out'the'reof from 6. In screw locking means a screw having a head the lower side of which is-provided 1 with aportion of less diameter than the ad joining upper portion thereof, the first named I3portion being or" cylindrical shape with its lower outer edge rounded and the lower side thereof having an annularfiat surface, the said adjoining upper portion constituting a shoulder the outer lower edge of which is rounded andtapered upwardly and the outer edge of said adj oining upper portion having notches therein, a fastening'washer adjustably mounted upon the said portion of less diameter said washer-having means-for en- ;"gaging a fixed member in adjoining relation to the screw, and means for engaging any one of the said notches.

In testimony that I claim the foregoing as my invention I have hereunto signed my "r name this 28th day of November, A. D. 1930.

V WILLIAM'JAMES GIBBONS.

the thickness of saidwasher being less than 

